The present invention relates generally to regulated DC-DC voltage converters, and more particularly to determining current in an inductor of a regulated DC-DC voltage converter.
Regulated DC-DC voltage converters generally provide for regulated power to operational circuitry, for example integrated circuits in semiconductor devices used in a wide variety of applications. Integrated circuits generally require provision of power within particular parameters during operation. The provision of such power may face many complexities. For example, semiconductor chips including the integrated circuits may have different portions that require power at the same or different times, different portions may require power within different parameters, and some portions may utilize different amounts of power at different times. Complicating matters, some devices may be powered by batteries having relatively small capacities, while the devices themselves, at least at various times, may require large amounts of power.
Provision of large amounts of power to integrated circuits may be potentially damaging to the devices. For this reason, and others, regulated voltage converters may attempt to monitor current provided to a load through an output inductor of the voltage converter. This may be accomplished, for example, by measuring a voltage drop across a resistive element in series with the output inductor. Unfortunately, such monitoring may result in excessive waste of available power if performed constantly, or even on a regular basis.
In addition, in many cases power requirements of the operational circuitry may vary greatly, and vary greatly within short time frames. Properly controlling converter operation in the face of sudden changes in desired output power may be difficult to accomplish. This difficulty may be increased if information regarding current being supplied by the converter towards the load is not available. Again, unfortunately, waste of available power to perform current monitoring may be particularly undesirable during times of sudden surges in desired output power.